Organic phosphorus compounds are well known polymer process stabilizers. For Example, Plastics Additives Handbook, 4th Ed., R. Gaechter, H. Mueller, Eds., 1993, pages 40-71, discusses the stabilization of polypropylene (PP) and polyethylene (PE).
Known phosphite and phosphonite stabilizers include for example triphenyl phosphite, diphenyl alkyl phosphites, phenyl dialkyl phosphites, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-α-cumylphenyl) pentaerythrtitol diphosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite (D), bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (E), bisisodecyloxy-pentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl) pentaerythritol diphosphite, bis(2,4,6-tri-tert-butylphenyl) pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl) 4,4′-biphenylene-diphosphonite (H), 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-dibenzo[d,f][1,3,2]dioxaphosphepin (C), 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenzo[d,g][1,3,2]dioxaphosphocin (A), bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite (G), 2,2′,2″-nitrilo[triethyltris(3,3′5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite] (B), bis(2,4-di-t-butylphenyl) octylphosphite, poly(4,4′-{2,2′-dimethyl-5,5′-di-t-butylphenylsulfide-}octylphosphite), poly(4,4′{-isopropylidenediphenol}-octylphosphite), poly(4,4′-{isopropylidenebis[2,6-d]bromophenol}-octylphosphite), poly(4,4′-{2,2′-dimethyl-5,5′-di-t-butylphenylsulfide}-pentaerythrityl diphosphite),

U.S. Pat. No. 3,096,345 is aimed at acetal and ketal phosphites.
U.S. Pat. No. 6,824,711 teaches tetraphenyl dipropylene glycol diphosphite and tetraphenyl polypropyleneglycol diphosphite, respectively. The target substrate is PVC.
U.S. Pat. No. 3,501,430 discloses tetrakis (nonylphenyl) polypropylene glycol diphosphite. The stabilizers disclosed are for halogen containing resins.
U.S. Pat. No. 3,829,396 is aimed at the stabilization of vinyl chloride resins and diolefin polymers such as butadiene styrene rubber and acrylonitrile butadiene styrene terpolymer. Tetrakis(2,4-di-t-butylphenyl) polypropylene glycol phosphite and tetrakis p-nonylphenyl tripropylene glycol diphosphite are disclosed.
U.S. published app. No. 2007/0254992 is aimed at the stabilization of polymers obtained from a water based latex or emulsion. Disclosed as a stabilizer is tetraphenyl dipropylene glycol diphosphite.
U.S. Pat. No. 7,067,570 is focused on one-part polysiloxane compositions. Phosphite triesters are one component.
JP2005170793 is aimed at organic polyisocyanate compositions. The compositions are stabilized with a combination of a phenol based antioxidant and an organic phosphite compound.
U.S. Pat. No. 4,371,646 is aimed at 2,6-di-tert-butyl phenyl phosphites.
U.S. Pat. No. 4,463,112 teaches organic polyphospites having at least two phosphite ester groups, at least one of which is linked through oxygen to a phenylethylidene-substituted phenyl group and to a residue of a polyhydroxy compound.
U.S. Pat. No. 5,322,871 teaches certain 2,4-di-tert-butyl-6-methyl phosphites.